Prenatal Growth & Functional Development Flashcards
Stages of prenatal growth
Period of the egg
period of the embryo
period of the fetus (longest)
Cell division in the period of the egg
*first 2wks after fertilization
1- Morula
2- blastocyst
3- implantation
4- Differentiation of cellular layers
Millestones in period of embryo
- wks 3-8
-differentiation of stem cells into specific cell types
-organization of cell types into tissues –>organs
-by end of period all basic anatomic and physiologic features established
Differentiation of stem cells into specific cell types
- totipotent (whole)
- Pluripotent (many)
- Multipotent (several)
Targets in period of the fetus
*wks 9-40
- changes in proportions
- functional dev of
1- tissues
2- organs
3- systems
growth characteristics
sigmoid curve
10-12% birth weight wk 20
50% length wk 20
What period features major changes in proportions of body segment
Fetal period
- head
- trunk
- lower extremities
Fetal motor activity gestational age specific
- neuromuscular changes, primary reflexes,
muscle tone,
reactivity,
Motility
sensorimotor behaviour
what wks they start to move
wk 12
kick wk 20